From patchwork Mon Jul 20 15:35:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 237541 Delivered-To: patch@linaro.org Received: by 2002:a92:d244:0:0:0:0:0 with SMTP id v4csp2124855ilg; Mon, 20 Jul 2020 09:21:37 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzrsJ4EC/rDCm8hjElJeHlpstP5YvhiwQGuTYJlVteR7MDncZfTaRUL4wmHRrmDHlFmUtNM X-Received: by 2002:a50:fd12:: with SMTP id i18mr22666426eds.371.1595262096938; Mon, 20 Jul 2020 09:21:36 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1595262096; cv=none; d=google.com; s=arc-20160816; b=VKmkmvK0HQ+n1uAEzTtQgIJHSYhE6FFeoeVSRZuVPID+WutdIsUPkxYF9/zHWAw9JY m1P4Kn0W+p+j68GHGLD7vezWufwBqdEyl1KYYD9cBo8DWb6hj93Y08alsK9zWsbO8L+s WlgkQTLXmork0g6zlyj2tbUFdBMSZhA7HyB7bv9jToZ22Lu5jLblxSlPtZix5Eu7h3qh cHkoxM2UXPShIOOQl78TKVSolRRdLOuOJZ2bRxNKGA8mbgdL3yUaUxQ92Zheby9OVGCK TYpnhoOdDJ5j3AlBC6KDZw8Cd9wiiZzqULn9ZTJOF+MGnM8koOoruuMLIEhaCtWuiCFx PrUg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=F3Lcrmec9BRco0Ex0e8TGKOHS0X74qoUUJlG17cDBkg=; b=EtBPFFNL9rdtfv9P5Q491gRW7YWsl9jQh6pq9vqTbNsuSx7v9gZxAd7kdB+nSAdVdn qJcEyqR0DuSI+ygMxeGTP5hsFWuRtr2yx6X1e3m/XrqS84LevrPg5jjTZOVDn0mYvdN6 XyzeaPXUP7aUPlMxfMMJkHOGJ6A2B7m8YeZs0sxnFNulx3E1E26N5+eJeoCgJ+uFCoAa BDTvzjDd7w2tHBivWcKLcn0XrPQNDmIalwlsB1ZatOObZtVSNO/3GmNUUCEv7DN8ZYTN xf47+1ZF3nAaJLa7bRbcqO7RdAl9eUIn7gx4WRXOKm+WqHsh70N1K1nsiXjEa72WQAA1 tlYw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=gCdrFOET; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id q18si10862861edr.440.2020.07.20.09.21.36; Mon, 20 Jul 2020 09:21:36 -0700 (PDT) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=gCdrFOET; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733226AbgGTQII (ORCPT + 15 others); Mon, 20 Jul 2020 12:08:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:45380 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732527AbgGTQIH (ORCPT ); Mon, 20 Jul 2020 12:08:07 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4F5962065E; Mon, 20 Jul 2020 16:08:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595261286; bh=6A7pUNuFUs6rSN73jvhbreK2J1VkrLL4f5bZyC7umC0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gCdrFOETEPGRavoXX0UmLlRigGCoLJtMkEs9ASJdjcD+NsMpHZAmf3F0heZzMEm74 WaRQ2pElI3UrEJ3OUywU++/nvFITb95R/g3D9R4se5uuIOTXReIPDmOWN8KJZlVE6S APEwO7af24HVudKPQAPVLRhqT/UbH9rQEpp4whkU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lars-Peter Clausen , Matt Ranostay , Alison Schofield , Jonathan Cameron , Stable@vger.kernel.org Subject: [PATCH 5.7 061/244] iio:humidity:hdc100x Fix alignment and data leak issues Date: Mon, 20 Jul 2020 17:35:32 +0200 Message-Id: <20200720152828.757780064@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200720152825.863040590@linuxfoundation.org> References: <20200720152825.863040590@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jonathan Cameron commit ea5e7a7bb6205d24371373cd80325db1bc15eded upstream. One of a class of bugs pointed out by Lars in a recent review. iio_push_to_buffers_with_timestamp assumes the buffer used is aligned to the size of the timestamp (8 bytes). This is not guaranteed in this driver which uses an array of smaller elements on the stack. As Lars also noted this anti pattern can involve a leak of data to userspace and that indeed can happen here. We close both issues by moving to a suitable structure in the iio_priv() data. This data is allocated with kzalloc so no data can leak apart from previous readings. Fixes: 16bf793f86b2 ("iio: humidity: hdc100x: add triggered buffer support for HDC100X") Reported-by: Lars-Peter Clausen Acked-by: Matt Ranostay Cc: Alison Schofield Signed-off-by: Jonathan Cameron Cc: Signed-off-by: Greg Kroah-Hartman --- drivers/iio/humidity/hdc100x.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) --- a/drivers/iio/humidity/hdc100x.c +++ b/drivers/iio/humidity/hdc100x.c @@ -38,6 +38,11 @@ struct hdc100x_data { /* integration time of the sensor */ int adc_int_us[2]; + /* Ensure natural alignment of timestamp */ + struct { + __be16 channels[2]; + s64 ts __aligned(8); + } scan; }; /* integration time in us */ @@ -322,7 +327,6 @@ static irqreturn_t hdc100x_trigger_handl struct i2c_client *client = data->client; int delay = data->adc_int_us[0] + data->adc_int_us[1]; int ret; - s16 buf[8]; /* 2x s16 + padding + 8 byte timestamp */ /* dual read starts at temp register */ mutex_lock(&data->lock); @@ -333,13 +337,13 @@ static irqreturn_t hdc100x_trigger_handl } usleep_range(delay, delay + 1000); - ret = i2c_master_recv(client, (u8 *)buf, 4); + ret = i2c_master_recv(client, (u8 *)data->scan.channels, 4); if (ret < 0) { dev_err(&client->dev, "cannot read sensor data\n"); goto err; } - iio_push_to_buffers_with_timestamp(indio_dev, buf, + iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, iio_get_time_ns(indio_dev)); err: mutex_unlock(&data->lock);